2014 Mazda 6 Advanced Package: How Much Better MPG With i-ELOOP?

The quest toward better gas mileage and incremental gains isn't relegated just to engine and transmission improvements, or to aerodynamics or weight reduction. Even when we're not talking hybrids, the move to smart electric components can bring some significant gains.

Beyond electric power steering, so-called 'smart' alternators are a next step that a number of automakers have already taken. But in the 2014 Mazda 6 is leapfrogging that, with a radical new brake-energy regeneration system called i-ELOOP.

It's making its world debut in the 2014 Mazda 6, and it's the first such system to use a special double-layer capacitor—not a battery—to quickly store away energy during times when you're coasting, decelerating, or braking. Then when accelerating, the variable-voltage alternator runs at its lowest capacity (and load), releasing energy from the capacitor to run accessories.

Capacitors for bigger mileage gains

Simply put, batteries are limited in how quickly they can store energy; on the other hand, storing or releasing a charge quite rapidly is a strength of capacitors. According to Mazda, there's about a ten-percent accessory loss in the act of generating electricity, and the automaker aims to recover much of that with i-ELOOP.

Mazda confirms that the system works much like the system that BMW had, a few years ago on introduction, called Brake Energy Regeneration (and now implemented throughout that luxury automaker's model line); although Mazda should be able to make an even more significant impact on fuel-efficiency thanks to the capacitor storage. As the automaker notes in a video (see below): “i-ELOOP closes the broken energy loop.”

Although Mazda originally touted i-ELOOP as a technology that's complementary to the company's 'i-Stop' engine start/stop system, as part of its SkyActiv suite of efficiency-related technologies, the automaker still has no plans to bring i-Stop here to the U.S.

We expect that i-ELOOP itself will produce better numbers for the Mazda 6. And according to U.S. spokesman Jeremy Barnes, gains from the system will be greatest on the highway, where the system most helps reduce the load on the engine.

The normal 2014 Mazda 6 lineup earns EPA ratings of 26 mpg city, 38 highway with the six-speed automatic transmission, or 25/37 mpg. With a diesel version of the Mazda 6 on the way—and likely more fuel-efficient than the gasoline version—the boost from i-ELOOP could give the '6' the highest-mileage lineup of non-hybrid mid-size sedans.

Is it worth a Hybrid price?

Now for the second caveat: i-ELOOP won't either be a standard system on the model; rather, it's only offered on the 2014 Mazda 6 Grand Touring ($30,290), as part of the upcoming Advanced Package, which will also include Radar Cruise Control (MRCC), Forward Obstruction Warning (FOW), Lane Departure Warning (LDW), and High Beam Control (HBC).

That, admittedly, will place the i-ELOOP Mazda 6 in the same pricing range as a well-equipped Ford Fusion Hybrid or Toyota Camry Hybrid.

Mazda plans to begin building U.S.-bound Mazda 6 models with the system beginning in May, and first deliveries start this summer.